Monster High/ Gravity Falls OOC Crossover: The Flopstar's Lover.

Billy Cipher, the twin sister (but not really) of Bill Cipher is fed up with life. Her family doesn't understand her and the kids at school are bullies. One day, Billy gets tickets to see her dream boy live in concert: Jin (the male version of Jinafire) What will happen???
These characters are very OOC but do share similar qualities to the actual characters. Other than the OCs, all rights to the owners of Gravity Falls and Monster High.
Rated Mature just in case. NOT SMUT.